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Canvas Clock Face


Part II - Draw a Clock Face

The clock needs a clock face. Create a JavaScript function to draw a clock face:

JavaScript:

function drawClock() {
  drawFace(ctx, radius);
}

function drawFace(ctx, radius) {
  var grad;

  ctx.beginPath();
  ctx.arc(0, 0, radius, 0, 2 * Math.PI);
  ctx.fillStyle = 'white';
  ctx.fill();

  grad = ctx.createRadialGradient(0, 0 ,radius * 0.95, 0, 0, radius * 1.05);
  grad.addColorStop(0, '#333');
  grad.addColorStop(0.5, 'white');
  grad.addColorStop(1, '#333');
  ctx.strokeStyle = grad;
  ctx.lineWidth = radius*0.1;
  ctx.stroke();

  ctx.beginPath();
  ctx.arc(0, 0, radius * 0.1, 0, 2 * Math.PI);
  ctx.fillStyle = '#333';
  ctx.fill();
}
Try it Yourself »


Code Explained

Create a drawFace() function for drawing the clock face:

function drawClock() {
  drawFace(ctx, radius);
}

function drawFace(ctx, radius) {
}

Draw the white circle:

ctx.beginPath();
ctx.arc(0, 0, radius, 0, 2 * Math.PI);
ctx.fillStyle = 'white';
ctx.fill();

Create a radial gradient (95% and 105% of original clock radius):

grad = ctx.createRadialGradient(0, 0, radius * 0.95, 0, 0, radius * 1.05);

Create 3 color stops, corresponding with the inner, middle, and outer edge of the arc:

grad.addColorStop(0, '#333');
grad.addColorStop(0.5, 'white');
grad.addColorStop(1, '#333');

The color stops create a 3D effect.

Define the gradient as the stroke style of the drawing object:

ctx.strokeStyle = grad;

Define the line width of the drawing object (10% of radius):

ctx.lineWidth = radius * 0.1;

Draw the circle:

ctx.stroke();

Draw the clock center:

ctx.beginPath();
ctx.arc(0, 0, radius * 0.1, 0, 2 * Math.PI);
ctx.fillStyle = '#333';
ctx.fill();